needs. Modeling will pare down the vast number of offerings to the best one or two options. From that data, the
confidence level of package prototypes for physical testing
validation is enhanced and reduces both time and cost.

In fact, parallel package design efforts can be initiated during
the testing phase since the confidence in the barrier solution
is so high. Modeling allows the compatibility of materials,
product processing, as well as storage and distribution, to be
factored into meeting the required shelf life performance.

PTI has developed a smart phone app that helps users
detect the oxygen permeation level of their packaging.
How does this app work, and how can it help manufacturers improve shelf life?

Q:

The PackLifeO2 app is based on the M-Rule® model. It
is designed as a “back of envelope” calculator for specific
materials and combinations. While it’s not an absolute decision making tool, it does give users confirmation that they
are headed in the right direction.

A:

The app contains five input sections — material, layers,
concentration, conditions and results —designed help the
user quickly input data and obtain oxygen permeation
results for their specific container. The first screen
asks the user to identify the packaging dimensions
(surface area and capacity). Next, variables for material and thickness are entered. (Up to three layers
can be used for the calculation.) The user selects
the material options from a pull down menu. These
include polyethylene therephthalate, low-density polyethylene, polypropylene, polycarbonate and nylon 6.
(The selections default to predetermined crystalinities
which may or may not be representative of what is
being used in the specific structure being evaluated.)
Each layer’s thickness in centimeters is also input.

The next screen asks for input of initial internal and
external oxygen concentration at weight per volume
parts per million. This is followed by temperature (
relative humidity is preset at 50 percent) and time (number
of days) over which the oxygen permeation should be
calculated. With those inputs in place, the user clicks on
“graph” to pull up the next screen which displays what
happens to the parts per million of internal oxygen as
the package is virtually subjected to the predetermined
test period. There is also a follow-up screen which displays a summary.